cessy

Have you seen a fish that could close their eyes while sleeping? As a kid, I often watch our aquarium at night to see how the fish sleeps and I never saw a single fish that shuts their eye when sleeping.

phil

A fish has no eyelid so he is not able to shut his eyes. Therefore it is hard for us to realise when they sleep or when not. It's a miracle for me how they keep on swimming during the sleep.

dana

It is somehow strange. Because there is streaming and when they don't want to end miles away from the place where they are right now they have to move and swim in their sleep, too. Or how does it work ?

trixie

I guess fish are atsleep when you turn off the aquarium's light so you may not able to see them if they are really sleeping. If they dont move then I guess they are taking a rest too.

cessy

Thanks Phil. I never thought that they lacked eyelids. Fishes are still swimming while asleep? Or is it that they get drifted to a different place because their body is so relaxed?